Unlocking doors (you will be warned first). It is often thought that the watch will not object if you use a skeleton key. In fact, using a key is no different from using a lock pick or credit card, except in that it will open a lock in a single turn, reducing the chance that a watchman will notice you doing so.

Some of these actions will not anger a watchman as long as he isn't in eyesight. Consult the entry on Minetown for a full discussion of the laws and ordinances in force.

In addition, attacking a peaceful watchman or a shopkeeper with a spell or wand does not anger all the guards; only the target of the attack. The watchmen are quite easy to kill (even easier than shopkeepers), and they have some potentially useful items in their inventory, although they often have a cursed item, so check all items on an altar or with a pet first. The watch captains are much harder to kill, but not as hard as shopkeepers. So don't do anything that will anger all the watchmen.

If you do run into any problems with watchmen, or you just want them out of your way without having to commit murder, you can usually buy a key from a Minetown shop and then use it to lock the watchmen inside one of the empty rooms.
One can also lure the watchmen to other levels via having them follow you to an up or down stair. If they are adjacent to you when you use the stairs, they will follow you to the next area, at which point you can 'lose' them in the new level, and return to Minetown while they remain in the other area.
You can also get shopkeepers to kill them by using a ring of conflict, anger the watch (preferably individually with a spell/wand), go into a shop, pick up an item so the shopkeeper blocks the door, stand one square away, and put on your ring of conflict. The watchmen will try to enter the shop to get you, and be slaughtered by the shopkeeper. The watch captain can kill a weakened shopkeeper so be sure to have some way to escape the watch captain, such as a wand of sleep, digging or teleport, or be fast and tough enough to slip past him, and get a second shopkeeper to finish the job.

Pacifying all hostile shopkeepers by paying them off also pacifies any angry watchmen on the level, so you can pacify all the watchpeople in mine town by stealing something inexpensive (a gold piece) from a shop and paying for it when the angry shopkeeper comes after you.

Do not bother killing watchmen to sacrifice them, even if you are a chaotic non-human: angering and killing them gives you a huge alignment hit because they count as "peaceful monsters of always-peaceful type", much larger than the alignment regained from sacrificing them. It is fine to have your pet or (with conflict) the watch captain or priest kill them, though.